STATEMENT OF WORK-TEMP.doc

DESIGN ANALYSIS REPORT

SECTION II

SCOPE OF WORK

RPR ROOF BUILDING No. 877

INCIRLIK AIR BASE, ADANA/TURKEY

PROJECT NO. LJYC 10-1015

3.2.15 Information gathered from various manufacturers.

3.3 DESIGN CRITERIA’S

The aim of the project is to renovate the existing roof of Building No.877 in order to avoid the leakage and to install a new Lightning Protection System for the building. The requirements of the abovementioned references, and requirements of the user representatives outlined during the pre-design meeting, future requirements of the facility, security measures, economic factors and durability of the construction materials are utilized during the preparation of the 65% design submittal package of the project. During the selection of the construction and finishing materials, durability, function, aesthetics and economic concerns will be considered to be the main design determinants.

3.4 WORKS TO BE DONE

Brief explanations of the works to be done on the building elements and finishing materials are given below:

3.4.1 Existing Condition:

Building No 877 has a prefabricated reinforced concrete structure with a ceiling slab consisting of pre-tensioned slab members supported by prefabricated reinforced concrete beams. The building has a trapezoidal sheet metal roof supported by steel roof trusses that form five (5) separate bays separated from each other by valleys at roof transitions. There are various metal

HVAC equipment supports and catwalks on the roof. The existing trapezoidal roofing panels are generally in good condition, however the polyethylene caps of the connection screws are deteriorated and the holes of the connection screws were deformed and enlarged due to the thermal movements in the roofing panels. These failures are add-ups to the leakage problems that are mainly caused by the deteriorated metal linings / flashings and wrong slope of the valleys which causes to the accumulation of water.

During the site investigations, the roof of building No.877 has been topographically surveyed and it has been observed that most of the valleys have slopes in opposite directions which should be sloping towards the downspouts that are on the exterior walls of the building, because of this failure water accumulates at the opposite ends of the valleys and sweeps into the attic trough the joints of the valleys which have poor connections.

3.4.2 Works to be Performed:

3.4.2.1 Roof:

During the execution of work the building will be in service, all roof mounted HVAC equipment will remain and will keep on operating, therefore all works related with roofing replacement and repair will be conducted in phases, works will be scheduled to keep the roof always closed against unexpected rain and other natural effects. The structure and design of the roof avails the phasing of the work without interrupting the building service.

The repair works will include the maintenance of the existing steel roof trusses, purlins bracings etc. These members will be sanded to be free from all rust and laitance and will be primed and painted with minimum two coats of synthetic based paints. With the 35% design package of the project, new 40x60x2 mm tubular steel purlins were shown to be installed between the existing purlins to reduce the purlin spacing to 60 cm from 120 cm. However after various discussions and studies of the manufacturers the subject purlins were decided to be eliminated.

All existing trapezoidal sheet metal roofing panels, all related flashings such as eave pieces, edge / apron flashings of the bays of the roof will be completely removed and replaced with new

0.7 mm thick, double hot dip galvanized and coil coated, standing seam type roofing panels.

The standing seam type roofing system will be constructed at the site by installing two separate layers of roofing panels. The first layer will consist of 0.7 mm thick hot dip galvanized trapezoidal steel sheet panels that will be installed on existing purlins with self tapping screws. Upon the completion of the installation of the trapezoidal roofing panels, sheet steel “z” profiles will be installed on the trapezoidal panels with self tapping screws, then the final 0.7 mm thick double hot dip galvanized and coil coated panels will be overlaid and seams will be formed at the adjoining lines of panels by utilizing special bending tools.

The new gutter flashings of the valleys will be 2 mm thick double hot dip galvanized and coil coated steel sheet, rectangular in shape, having a width of 25 cm and a minimum depth of 15

cm. The ridge flashings shall be 0.7 mm thick hot dip galvanized and coil coated sheet steel. All flashings, ridge pieces, “z” profiles and installation accessories shall be the standard products of the roofing panel manufacturer.

3.4.2.2 Gutters: As it is mentioned above the building has steel sheet gutters at the perimeter and valleys formed by the roofing bays. During the repair works, all gutters, their hangers, related flashings etc. will be removed and replaced with new by providing proper slopes towards the discharge points. Gutters at the valleys will be rectangular in shape formed from 2 mm thick hot dip galvanized and coil coated sheet steel, having overlapping side flashings extending minimum 50 cm towards the undersides of the adjoining roofing panels. The connections of the gutters at the valleys shall be done by welding. Therefore 50 mm of the edge to be welded will not be coil coated, and galvanized sheet metal will be left exposed. Upon the completion of the welding works, effected edges will be cleaned, touched up with zinc rick galvanizing repair paints and painted with the type of paints that will be recommended by the manufacturer. Gutters at the eaves of the building will be 150 mm diameter, 0.9 mm thick hot dip galvanized and coil coated sheet steel, with hot dip galvanized sheet metal hangers spaced at 50 cm intervals and 0.7 mm thick galvanized and coil coated apron flashings. Rivets and sealing compounds shall be used for connecting gutters. Apron flashings will also be connected to each other by means of rivets and seals. Strainers will not be used in gutters due to the clogging problems caused by leaves and debris.

3.4.2.3 Downspouts: The existing downspouts of the building directly discharge on the sidewalks and existing grade, as it has been requested during the 35% design review meeting a new subsurface drainage system shall be provided and the new downspouts shall be connected to the new storm drain lines trough reinforced concrete discharge boxes. The new downspouts of the building will be 250 mm. diameter, 1.5 mm thick hot dip galvanized and coil coated sheet steel. As it has been requested with the comments of the 35% Design phase, the downspouts of the building will be connected to the existing underground storm drainage system of the site.

Therefore the existing closest catch basins shall be utilized for the necessary connection. New reinforced concrete connection boxes shall be provided at the discharge point of each downspout. The subject collection boxes will be connected to each other and to the existing catch basins with 300 mm diameter PVC underground storm drain lines. The new downspouts will be tied to the connection boxes trough cast iron downspout boots.

END OF SECTION